The problem its when I tried tje second altboot for boot from the sd card, appear:

modpobe: FATAL: could not load /Lib/modules/2.6.23/modules.dep: No such file or directory Note: No init (/sbin/init.sysvinit) found on target Note: No boot-images found in /media/card/boot-images ERROR: No direct-install or loop-images foud. Nothing to do!

You're asked if you want to flash the kernel, erase the flash, flash the root filesystem and finally the Android root filesystem. You can except all questions with the defaults (all yes). Only the last bit, the extraction of the Android root filesystem, doesn't work (yet). It doesn't seem to be possible to extract a tar archive to an ext3 formatted SD from the flashing environment (Permission denied). We need to do an extra step because of that unfortunately.

After flashing the Zaurus is rebooted automatically and Altboot is started. First time you need to enter a specific Altboot password. After that, choose option 1 so the Zaurus boots from internal flash memory. Login with root and extract the android root filesystem manually.

cd /media/cardtar -xzpf android-root.tar.gz

Depending on the speed of your SD card this can take a while.

Now, I found out the best way to handle now is doing a full reset (power off, battery remove, 5sec wait, replace battery and power on). The Zaurus boots, and when Altboot starts choose option 3, boot from SD. The first time you do this you'll be asked if you want to copy the home directory. Answer yes to this question!